This invention relates to filtering machines and more particularly to an apparatus for separating loose pieces of paper from a caustic soda solution.
There has long been a need for an apparatus to cooperate with a bottle washing machine having a plurality of washing tanks, so that at the end of a washing cycle, the mixture of caustic soda and labels removed from the bottles may be passed through label disposal and caustic filter so as to remove all of the labels from the mixture and return the caustic soda substantially filtered to the washing machine tank again.
Prior machines of the above type have proved to be somewhat ineffective in their filtering ability and are most difficult to clean.
Therefore, it is an object of the invention to provide an apparatus for separating loose pieces of paper from a caustic soda solution that is highly effective in its filtering ability.
A further object of the invention is to provide an apparatus of the above type that is easy to clean.
A further object of the invention is to provide an apparatus of the above type that is simple in construction, inexpensive to manufacture, and highly effective in operation.
Briefly, the foregoing objects are accomplished by the provision of an apparatus for separating loose paper pieces from a solution of caustic soda including a tank with an elongated solid plate hopper operatively disposed at the top of the tank (interiorly thereof) for receiving a caustic solution mixed with paper pieces and having an elongated converged bottom opening defined in part by two spaced parallel bottom hopper edges positioned intermediate the top and bottom of the tank.
Pump and manifold means are provided for directing caustic solution mixed with paper pieces into the hopper. An elongated helical screw conveyor is operatively disposed below and spaced from the hopper bottom opening in parallel spaced relation thereto for feeding paper pieces to the tank exterior. Conveyor drive means is provided for driving the helical screw conveyor when desired. Also provided is a pair of coacting elongated rotatable cylindrical stainless steel screen-type perforated hollow drums which are spaced from each other to provide a space therebetween and are operatively positioned in the hopper bottom opening above and parallel to the helical screw conveyor for receiving from the hopper caustic solution mixed with paper pieces on the outer cylindrical surfaces of the drums and directing the paper pieces into the space between the drums and into the screw conveyor. The drums also receive caustic solution through the perforations in the drums and direct the solution to the bottom of the tank. Drum rotating means are provided for rotating the drums about their longitudinal axes. An elongated hollow stainless steel cylindrical screen type filter is disposed at the bottom of the tank for final filtering of the caustic solution and for directing the filtered solution to an associated storage container exteriorly of the tank.
In operation, a caustic soda solution mixed with paper pieces is fed by the pump and manifold means into the hopper and thence discharged by gravity onto the rotating drums which feed the paper pieces on the outer drum (rotary) surfaces into the conveyor and thence to the exterior of the tank. The caustic soda solution flows through the perforations in the drums and thence to the bottom of the tank and thence through the cylindrical filter for final filtering and thence to an associated storage container exteriorly of the tank.
The screen-type filter is covered with a nylon cloth to filter the caustic solution to 125 microns.
A vertical screw conveyor is operatively secured to the discharge of the elongated helical screw conveyor for transporting the paper pieces from the elongated helical screw conveyor up above the apparatus and onto an associated conveyor chute. Each of the drums has manifold piping secured to at least one of the ends thereof for feeding caustic solution from the drum interiors to the bottom of the tank. Brushes are secured to said bottom hopper edges and extend downwardly therefrom and operatively contact the drums to clean the outer surfaces of the drums and forestall clogging of the drum perforations. Also, a brush is secured to a bottom wall of the tank interiorly thereof and operatively contacts the filter to clean the exterior surface thereof. Spray flushing pipes extend axially and interiorly of each drum and of the filter for flush cleaning the same. A pressurized liquid supply means communicates with each such pipe.
Other and advantages of the invention will be apparent from the following description taken in conjunction with the drawings wherein: